Association of complex genotypes of kappa-casein and diacylglycerol O-acyltransferase from milk production in different lines cows

Abstract

Abstract The aim of the investigation was to observe the frequency of complex genotypes CSN3/DGAT1 occurrence and their effect on the milk production of different lines cows. It was found that in the herd of cows 4 genotypes CSN3 AA / DGAT1 AK and CSN3 AB / DGAT1 AA, CSN3 AA / DGAT1 AA, CSN3 AB / DGAT1 AK predominate with a frequency of occurrence of more than 7.3%, notably that the greatest number of combinations are found in the lines of M. Chiftein and R. Sowering. The best indices of milk yield (5736 and 5401 kg), milk fat (208 and 201 kg), milk protein (179 and 170 kg) in the lines of V.B. Aydial and R. Sowering were noted in first-calf heifers with the AB/AK genotype. A significant difference (P < 0.05-0.01) in milk yield, fat and protein in the Sowering line was found between the combinations AB/AK and AA/AA, and AB/AK and AB/KK. In M. Chiftein’s line, the highest milk yield (5045 kg), milk fat (182 kg) and protein (163 kg) were detected in the CSN3 BB / DGAT1 AA genotype, when exceeding the combination of AA/AA and AA/AK (P < 0.05-0.01). In high-producing cows V.B. Aydial’s line has the highest milk productivity in cows with the genotype CSN3 AA / DGAT1 AA, when animals with the genotypes AB/AK and AB/KK are exceeded (P < 0.05-0.01).